Recently, the following data processor has become widespread. The data processor detects characters described in an advertising display, a sign, a paper, etc., from an image captured by a camera and applies a character recognition process and a translation process to the detected characters. When using the data processor, the user needs to recognize where is currently captured by the camera through the preview screen displayed on the display, move the camera (data processor) toward the characters to be captured and set the characters so as to be within the imaging range. This process is called framing.
The framing process can be more easily performed as the time required until preview display which displays the preview screen on, the display is shorter (in other words, as the refresh rate of preview display is higher). However, at the moment, every time an image is captured by the camera, characters are detected from the image, and further, a character recognition process or a translation process is performed for the detected characters. Thus, the refresh rate becomes low, thereby creating difficulty in the above framing process.